Classifying table



March 28, 1933. STUMP 1,902,917

CLASSIFYING TABLE Filed Dec. 13, 1929 [71 yen for iarZ. fizam a .izfarieeyls.

Patented Mar. 28, 1933 umrau- STATES PATENT orrlcs EARL STUMP, OI CHICAGO, ILLINOIS, ASSIGNOR TO ROBERTS AND SCKAEFEB OOH!- PM, OF CHICAGO, ILLINOIS,

A. CORPORATION 01' ILLINOIS GLASSIFYING TABLE Application flied December 18, 1929. Serial No. 418,715.

This invention relates to a material separating plant. In the form illustrated herewith it is shown as applied to a coal cleaning table in which coal is cleaned and separated from refuse and foreign matter. The invention is not limited to this application but for convenience it is shown in connection with this dry cleaning table or drying classifier. It has for one object to provide automatic means whereby the supply of air to the cleaning table is automatica ly controlled in response to the feed of material to the table itself. One object of the invention is, therefore, to cause the material to control the supply of air. Another object is to provide a mechanism whereby the quantity or the speed of the fiow of material to the table will vary and control the quantity of air supplied to the table.

Other objects will a pear from time to time in the course of t e specification and claims.

The invention is illustrated in the figure more or less diagrammatically. The figure is a side elevation of an air cleaning table assembly with parts in section and parts omitted.

A indicates an air conduit by means of which air is supplied to a funnel-shaped member A from which it is dischar ed through the cleaning surface A of the ta le.

B is a butterfly valve fixed to a shaft B which is controlled by a lever B. Rotation of the shaft moves the valve and so controls the supply of air to the entire assembly. The parts are normally so shaped that when the automatic control is in operation the valve will be slightly open at all times and thus some air will constantly be passing into the conduit and through the surface of the table.

C indicates a feed trough or chute by means of which material such as coal will be fed to the cleaning table.

I shall now describe the automatic separating means whereby the butterfly valve is moved to control the supply-of air to the table response to the feed of material to the table.

D isa link pivoted as at D at its lower end and joined as at D at its upper end to a lever arm D. D is a second link fastened to the lever arm D at a point separated from its pivoted point. D is a link member fastened at one end adjacent the outer end of the lever B and fastened at its upper end to the lever D preferably between the points D and D. D is a second lever armattached to the pivotally mounted shaft D and being connected at one end to the link D and car ing adjacent to its other end acounter weig it D. D is a switch ada ted to be contacted by the end of the lever when it is raised. The switch D is normally arranged to control the operation of the jigging or movingmechanism for the table, so that when the switch is in one position jigging movement of the table is carried out by the appropriate mechanism for that pur ose and when it is thrown into another positlon by the action of the lever arm D, the jiggin mechanism is thrown out of operation and t e motion of the table is stopped. D is a gate attached to the pivotall mounted shaft D' and extending into t e path of material flowing downwardly along the chute C onto the table. Material, as it flows downwardly, strikes the gate D and swings it outwardly.

The use and operation of my invention 3 are as follows:

When the device is in operation the parts will be more or less as shown. The means for moving the table is active and the table is in motion. Air is supplied from below and passes upward from the table. Material moves downwardly along the feed trough or chute, passes outwardly across the table and under the influence of the air, and the motion of the table is separatedand classified. The particular details of this action form no part of the present invention and will not be further described. It is sufiicient to state that the material is separated and classified and cleaned by the action of the table.

When the material is being fed toward the table with sufiicient speed and in suflicient quantities, the gate flap is held 0 en. This rotates the shaft D counter-clove wise and moves the free end of the lever D away ing the left handend of the lever D, the

' link-D and the left hand end of the lever B linkage above described will cause movement of the valve either to increase or decrease the supply of air. As the feed is reduced, the gate moves again in a clockwise direction and the valve is'partially closed. If the feed is entirely stopped, the movement of the gate is sufficient to shut off all but a minimum of the .air and also to permit the lever arm'to strike the switch and stop the operation of I the jigging or table moving mechanism.

It is desirable to prevent a complete clearing of the table, that is to say, to prevent a complete discharge of all material from the table. Parts are so proportioned. therefore,

that the switch which controls the table driving mechanism will'be operated to cut oil that mechanism before the feed of material to the table has completely stopped. Even though the feed may have completely stopped and the motion of the table has been stopped. it is desirable to keep the bed of material which remains on the table in motion. Among. other reasons, this is done to keep the cloth of the table dry. For that reason the parts are so proportioned that the valve cannot automatically be completely closed and at its minimum setting it is slightly open so that sufiicient air can pass through to keep the material which remains on the table in motion. y

The mechanism which I have described above. will act in response to variation of the feed. the quantitv of the feed and the speed of the feed. If the quality of the ma terial fed remains the same as to size and dryness no substantial variation of the position of the air controlling valve will take place. If the quantity ofthe material changes while the dryness and size of the material remains the same, a variation in the setting of the valve will be caused automatically. If the quantity and the size of the material remain the same but the relative dryness is changed, the speed of the flow of material will be altered since wet material flows more slowly than dry material and this change of speed will cause a change in the position of the gate D and corresponding- 1y by means of the mechanism of links and lever, will cause a change in the air valve setting; Thus the material, as it is fed, au tomatically controls the air fed in response quantity or its quality.

I chum:

1. In combination witha material classifiei', a continuous air supplying means therefor for forcing a constant sup 1y of air through the classifier, means for fgeding material thereto and regulating means tovary the volume of said air supply, adapted to operate automatically in response to variations in the feed of material to said dlassifier whereby the supply of air is adjusted in accordance with requirements on the classifier table due to variations in the feed of material thereto, said regulated means arranged to permit a minimum, of air to pass, irrespective of its setting.

2. In combination with a material classifying table, means for giving it motion, means for supplying air continuously to it, means for supplying material to be classified to it and means, responsive to variations in said material supply, adapted to vary the quantity of air and to stopthe mechanism for moving the table.-

3. In combination with a material classifying table, means for giving it motion, means for supplying air continuously to it, means for supplying material to be classified to it and means, responsive to variations in said material supply, adapted to vary the quantity of air and to sto and start the mechanism for moving the ta 1e. 1

4. In combination with a material classifying table means for giving it motion, means for supplying air to it and for forcin air through it, means for supplying material to be classified to it and automatic means, res onsive to variations in said material supp y, adapted to vary the quantity of air and to stop the table.

5. In combination with a material classifying table, means for giving it motion, means for supplying air to it, means for supplying material to be classified to it and means, responsive to variations in said material supp y, adapted to vary the quantity of air and to stop the mechanlsm for moving the table, the air supply being never reduced below a fixed minim 6. In combination with a material classifying table, means for giving it motion, means for supplying air to it, means for supplying material to be classified to it and means, re-

sponsive to variations in said material sup-' ply, adapted to vary the quantity of air and to stop and start the mechanism for moving the table, the air supply being never reduced below a fixed minimum.

7. In combination with a material classifying table, means for giving it motion, means for supplying air continuously to it and for forcing air through it, means for supplying material to be classified to it and automatic and start the mechanism for moving rial supply, adapted to vary the quantity of air supplied to the classifier table whereby the air supply is adjusted in accordance with requirements on the classifier table due to variations in the feed of material thereto, said last means bein arranged to prevent the reduction of air ow below a fixed minimum. Signed at Matoka, county of Mercer and State of West Virginia, this 15th day of November 1929.

EARL STUMP. 

